Yup Yup yup, had the similar problems with lofting out the Gt Auk currently being worked on. Found that it was easier to draw out my own grid, I did find an old steel ruler that had 1/10ths and 1/100ths on it. I think it came from my fathers collection of tools. NZ went metric in the 60's. But in moments of stress and panic the old imperial units surface. "The idiot missed me by an inch!" not 'The idiot missed me by 25mm'. Off topic I supose, but I found that converting left the possibility for errors to creep in. Nick drew it in inches, so leave it in inches.